The Michigan Street Lift Bridge reopened to vehicular traffic Friday, July 31, 2020, after a yearlong rehabilitation project. The bridge spans the Milwaukee River and is one of many downtown bridges that link Milwaukee, Wisconsin's East Town and Westown neighborhoods.
The City of Milwaukee’s Department of Public Works oversaw the project, which upgraded, and replaced as needed, the existing structural, hydraulic and mechanical components. The previous lift bridge had a latticework steel deck, which was replaced with concrete decks.
Parker Distributor MFP Automation Engineering was a key subcontractor in this large public works project. MFP Automation Engineering was founded in 1991 and specializes in pneumatics, hydraulic power units, custom manifolds, servo motors, motion control products, electromechanical and much more. Over the past five years or so, MFP has made a name for themselves for their involvement in several movable bridge projects. Their bid for the project was selected over other hydraulic suppliers in part due to their ability to supply a turn key system as part of their bid package.
Lift bridges and hydraulics go hand and handMFP supplied a custom-built hydraulic power unit, a directional control manifold, four large Parker cylinders, and installed all the associated plumbing. MFP was a valued partner to the large civil engineering firm for the project, and during the process was able to suggest some modifications to the original design.
Many Parker divisions provided key Parker products, which are now installed, ensuring that the hydraulics on the lift bridge operates as designed.
Hoses and fittings
Hose Products Division supplied the 387TC GlobalCore Hose and 43 Series Fittings that are used on the bridge. Parker’s 387 GlobalCore hose is a constant working pressure hydraulic hose offering 3,000 PSI in all sizes, ranging from ¼-inch to 2 inches in diameter. With three cover options: Standard, ToughCover, and SuperTough Cover, this light, durable, and easy-to-bend hose meets and exceeds ISO 18752 performance specifications.
The 387 hose offers low force-to-flex and delivers full SAE-standard pressure at one-half SAE bend radius, resulting in easier handling and installation. 387 hose also offers a 30 percent smaller OD by area compared with SAE-standard spiral hose and is compatible with petroleum-based hydraulic fluids and lubricating oils.
GlobalCore 387 hose is compatible with Parker’s 43 series fittings in sizes -4 to -20. The fittings feature one-piece construction with chromium-6-free plating, are offered in more than 2,500 configurations and are available around the world.
Hydraulic cylindersThe Cylinder Division was able to provide critical design insight and engineering assistance for this application, The cylinder required many special design characteristics to meet the stringent safety parameters on this project.
The hydraulic cylinder that is used on the bridge is based off of Parker’s 3HB series product. While this starts as a traditional NFPA product, the 3HB differs in that it does not utilize tie rods. This was extremely beneficial for the project since it eliminated the need for tie rod supports (there would have been several needed) and allowed for MFP’s custom manifold to be affixed to the cylinder body at an optimal location. The lack of tie rods and supports also reduces overall weight and makes maintenance much easier. The standard dual wear band design of the 3HB piston provides excellent bearing surface that will translate to long cylinder life.
System diagnostics and analysis
During the installation, MFP’s team utilized the Service Master Easy from the Quick Coupling Division to monitor the different cylinder pressures. The Service Master Easy is a convenient, easy to use, handheld meter that can measure four different pressure transducers simultaneously. The large screen readout allows the user to see if there are pressure drops (or spikes) in the hydraulic system.
The Service Master Easy is just one product in the division’s SensoControl product line. Being able to effectively monitor equipment systems and diagnose issues before they become problems can help alleviate costly downtime and prevent damage to expensive equipment. Parker SensoControl products gives end users an edge in downtime prevention with a full complement of condition monitoring and diagnostic equipment that is ideal for individual components or entire systems.
Gear pumps
Safety and reliability are necessary in a lift bridge, especially for a downtown city location. The Michigan Street Lift Bridge benefits from decades of Parker pump expertise. The Pump & Motor Division supplied the 365 Series gear pump for the project.
The 365 Series is a fixed displacement gear pump which offer high pressure durability due to its cast iron construction, making them ideal for high duty applications. The 395 Series Pump is ideal for critical applications due to the high horsepower and proven durability and efficiency.
Hydraulic valves
Smooth and reliable acceleration and deceleration control are critical to the safe operation of the bridge. The Hydraulic Valve Division’s D41FC series are installed as the pilot-operated proportional directional control valves to provide dependable, precise closed-loop control over a range of high flow rates. Additionally, the D41VW provides reliable on/off directional control of the system.
Milwaukee has rapidly changing weather with cold, windy, snowy winters and warm, humid summers. The lift bridge and its components need to withstand a variety of environmental conditions. The digital onboard electronics are situated in a robust metal housing, providing protection against these challenging elements, while also carrying an IP65 designation for the vibrational conditions.
Built to lastParker's distributor partnership with MFP Automation Engineering and many of Parker’s division engineering experts brought the Michigan Street lift bridge to life, and will be part of the city's infrastructure for years to come.
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